> The main advantage that Slack has, especially for many people in non-technical roles, is the just-professional-enough user interface over the casual look of Discord.

1) That's not much of a moat for Slack. If Discord were serious about entering the enterprise market, and there's sufficient user feedback on this point, I'm sure they could adapt with a few month's work.

2) I've heard similar critique about Slack in the past as well. IMHO professional vs casual comes down to expectation and familiarity. As more youths who are accustomed to Discord enter the workforce, the casual connotation would go away.

There was a time when e-mail was considered too casual and unfit for professional communication, too.